Rotation-meter.



E. A. LARSON.

ROTATION METER. APPLICATxoN msn MAR. 25, 1915.

Patented Feb. 6, i917.

UNITED sTATEs PATENT oEEioE.

EDWARD A. LARSON. OF'CHIOAGO, ILLIOIS, ASSIGNOR TO STEWART-WARNERsSPEED- @METER CORPORATION, OF OVHICAGOfILLINOIS, A CORPORATION OF VIRGINIA.

EoTATIomMETEn,

Specication of Letterslatent.

Patented Feb. 1917.

To all whom it may concern Be it known that I, Enwann A. LARsoN, a citizen of the United States, residing at Chicago, in the county of (look and State of illinois, have invented new and useful lmprovements in Rotation-Meters, of which the following is a speeilication, reference loeing had to the accompanying drawings, forming a part thereof.

This invention relates to a rotation meter especially designed to serve as a speedometer and odometer for use on motor vehicles.

lt consists of the specific features and arrangement of the parts desilribed and shown in the drawings as indicated by the claim.

in the drawings :HFigure l is a face elevation of an instrument embodying this invention. Fig. 2 is a vertical section on a larger scalexaken as indicated at line 2 L on Fig. 1. Fig. 3 is a front elevation of the interior mechanism, being taken as a section at line 3 3, on Fig. 2. Fig. 4 is a detail section taken as indicated airline ll on Fig. 3. Fig. 5 is a detail section taken as indicated at n,line 5 on Fig. Fig. is a detail view taken as a section at line (3 6 onsFig. 2.

The instrument shown in the drawings presents-,the usual combination of a speedometer for indicating the speed of travel, and an odometer for indicating the distance of travel ofthe vehicle on ,which it is mounted, hoth mechanisms being connected for act-uation by a single drive shaft. l, ordinarily arranged, to be driven from one. of the road wheels or other rotating parts by connections not shown. Such vehicles are generally provided with a dashboard or instrument board which is substantially vertical or slightly inclined to the vertical, and the speedometer is preferably mounted in the dashboard with its casing. 2, sunk in a properly litted aperture therein, bringing its face or dial, il, suhstantially flush with the board, or at least in a plane parallel thereto. Fig. shows a portion of the instrument board at al, thus illustrating this arrangen'ient. rl`he board, il, usually forms the back wall of the hood or bonnet covering the vehicle motor, and is therefore located at somedistance rearward of the forward road wheels, from one of which the speedometer is ordinarily driven tlnough suitable gears and a flexible shaft coiipled with the drive shaft, l. Thus by arranging ther'instrument with its drive shaft. 1. extending from the back of the casing, 2, substantially at right angles to tne plane of the dial, 3, the liexible shaft, not shown, which extends to the forward road wheel, may pass down through and out at thehottom of the motor hood almost in a direct line, or at least with the minimum of bending. f

The speedometer illustrated comprises the usual circula` magnet, 5, whose shaft, (i, is connected with the drive shaft, l, through bevel gears, 7, and whose speed of rotation. is indicated by the position of the cupshaped drag disk, 8, provided with the usual. hiasingspring, 9, and carryingr the dial nu merals in a position t0 appear at the window, e, of the dial, 3.

The odometer train operates upon the familiar Geneva stop principle. The worm, l, on the drive shaft, 1, meshes with a worm wheel, 10, rigid with a second worm, il, meshing with a second worm wheel or gear, 12, and the shaft of the gear, l2, is provided with a third worin, 13, which meshes with a gear, 14, thus giving the desired reduction of speed between the drive shaft, 1, and the odometer train. The gear, 1i, carries a larger gear, 15, which connects through idlers, 1G and 1T, with a gear, 1S, `fast on the hub, 19, of the first ntnnelral-bearing wheel,

20. A gear, 21,011 said numeral-hearing wheel is connectedv to a gear, 22, through idler gears, 23 and 2l, similar to and coaxial with the idlers, 1G and 1T, respectively;

rigid with the gear, 22, and separated from it by the spacing disk, 25, is a disk, 26, having a single notch, 2G, and rigid with this disk is a mutilated gear, 27, having only two teeth positioned to mesh with the longer teetli`,'28, of the idler, 2S. The shorter teetl 2%, alternate with the longer teeth, 282i, and

both series 'of teeth mesh with the gear 29 which is loose on the shaft of the gear, 22,

hut rigid with the next spacing disk, 30.

` Each revolution of the gear, 22, corresponds to one revolution'of the dial wheel,

20, and during each such revolution the notch, 26a, and the two teeth of the gear, 27,

meshing with one of the longer teeth, 28, of

the idler, 2S, rotate said idler by a `distance of two teeth, and such rotation is communi-l cated through the idler to the gear, 29, ad-

vancing said gear by a distance of two teeth,

which is preferably for this purpose equivalent to one-tenth of a revolution. The gear,

29, and its spacer," 30., are provided with a tix notched l; leeli. siin...r e "ehe elements, ani?. thai 'for eaeh revolution if the gearll, is proilueerl mie-l1eiil1h el a .rolaion of the neg'a succeeding gear, 3l, and .so on lirengholi; the en'lire eeoinelner train. la illustraeiil, the odometer izrain consists of iw@ Series @if ilial wheels and their eorreponding gears, the gears, 2Q, il and 3l, relaing' to 'the trip odometer, which may he reset independently oi" ilhe olher i; aiirsshewu loeatel at glie other aille oi' the actuating' gear, ll.

lfnyprei'ioufs coi 'infueiona the gear, Ll, has been connected rigidly willi the spacing; disk, 23, or gear., and lie spacing disli, 25, u.; well aa the other spacing flink similar tu t, have eonsiituteil the numeral hearingdial whe@ but with thi` arranggenienl the wiclh. oi the ilial wheels has been so limited on aecountA of the space necessarily eeeupiefl by the other elements of *che train, that is, the disk, 2G, he iuuiilai'iecl gear, 27, and the gear, QS), 'that the numerals imprinecl thereon were noi"l large enough to he eiwilyv readable and were spaced apart from each other by an undesirable anieun. `j`or this reason il; has been deemed preferable 'place 'the mi* inerals upon sepa *alge Wheela, like ibhe Wheel, 20, which eoulfl lie of about *die full wiilh of the g'oi'nbinei'l 1', 21T, the disk, '226, and Spa-- ing disk, Each of the numeral-bearing Wheels; is then fitted with a rigid gear like gear., 9,1, and operatively eonneced through idler ,gears such :i523 and 524, will: lie Correu sponrlingr gear lilie, of tElie "arain already described. Thus the necesary Space between eonaeeuiiii'e nuinejalfbearingr wheels is only :saillieient ilo a ilini; a coniparaively thin idler gear. ,auch as fallait Shown ai; 32, and the, aria available. for the numerals considerably increasedn s shown, the numeral-bearini wheels are also larger in diameter 'than fie spacing lh-,lis like Q5, so shat Jehe niinierals in circ:

inaj, he proportionately enlarge ieren'inil ilireei'yioii as?" well as in 5h15 'l tion al: lilie The trip odometer is ol Course inlzehilei" t he reset lo Zero or le any oher ilesireil reafling1 without changing; 'the reading' the total reggini'er. This ia aeeonipliehafl by means oill the shaft, 2323, ea Tying); lhe knurlecl wheel, ill', at iis outer enil, and a gear, 35, ai its inner cnil.y which will nieli with the 1gear, 2l, on thelirsl: dial Wheel, 20, when the sha'l pulled oufJ in the direction of its side of j anis a Sheri (limi lion with respect lo the caieh composed of a Hal A upon a hall, 3'4", which is (lessi either the groove, 2li-S", lie groove, 33", .in the Shaft, 233, servea'fz@ lefnilely position the gear, 35, in er oui; of' ei'igageinan Witli the gear, is h@ 5l inulleilL out to el'leet engagement of the and 23., its conical earn surface, operates agains 'the end, 38a, of the shi'fer lever, 38,

draw che idler gear, i6, ma", Gf :mesh i lhe gears, l5 and l?, thus disconnecting rip odoiueer from the aenialingg gear,

and from 'the oial ocloineer iin, se as m pei-nul. lha 'free roabion of imp dial.

wheels to an V ated in is 5, die enel, le, of the lever, 38, is clamped uo engage he head, 39"", ef the shifter red, 39, wLiei carries a extendinginte a groove, 16?, in. the hub of the gear, 16, for sliifing' the laizer in an ollvious manner. The Shaji, 33, is preferably arranged i0 prejee' direely out from the ilial plabe, 3, thus keeping ii Within the, eireular outline lille insi'un'ient casing, 2, and siii'iplifyiin,;L rhemnuning elf "alle in# inalruinenbeard, ll, A

strunieu in "alle,

hashing, -l-O, serves as a bearing for the shaft, and is; formed with a lan alla,

slightly groovecl. or "undercut al 4Gb, Le rn eeive @ement 'for `ecm-"ing it i0 'the surfree of the glass, il, covering' the (lial plata, elaiin il meter comprising a easii a dial covering the front or" the easing; a glais on one 'wie dial, and indiealor meehanisms, all oi' which are on ehe other side of the dial; operating mechanisms for lie inclii;L i301- nfiechanisin, a iii-.setting key which iiaSSes lzhi'ougli the dial am 'the and which is.

normally fliseonneeel liinin the inlicaor iueelninwin hul` which longimdinallv mov zhle for roinieeuni il rewith, and means (lisouneel ig the inzliealor mechanism from Jdie einem ineehaninis when ithe key i5 longitudinalllv moreel.

in 'lestiinony where have hereunto Set my hand ai Cliiea i, llinois, this 22nd (la).y el ill-arch, 15H5.

"lll/liiiesses lon'r. hl. BURTON,

desired poeiior, is nullfinger, 39",' 

